Dietary and Lifestyle Determinants of Vitamin D Status in Filipino Women Living in Korea: FiLWHEL Study

Abstract

Objective We aimed to assess vitamin D status and to identify dietary and lifestyle determinants for vitamin D status among Filipino women living in Korea of the Filipino Women's Diet and Health Study (FiLWHEL).

Methods Filipino women who have been married to Korean men were recruited from March 2014 to April 2016. We included a total of 486 Filipino women aged 20–55 years old in our analysis. Serum levels of 25 hydroxyvitamin D (25(OH)D) were measured using electrochemiluuminescence immunoassay. We asked participants about demographic and lifestyle factors through face-to-face interview and assessed anthropometric measures using bioimpedance method. We identified dietary, demographic, anthropometric, and lifestyle factors associated with circulating 25(OH)D levels using the linear regression model. We included variables of which significance levels were under 0.1 in the univariate model and examined whether these variables were statistically significant at an alpha of 0.05 in the multivariate model.

Results Mean serum 25(OH)D level was 15.4 ng/mL (SD= 6.4). The prevalences of severe deficiency (<10 ng/mL), mild to moderate deficiency (10–<20 ng/mL), and insufficiency (20–<30 ng/mL) of vitamin D in this population were as follows; 17.5%, 63.6%, and 16.5%. Vitamin D intake from food and supplements (β=2.56, p=0.008), season of blood draw (fall vs. spring; β=0.22, p<.0001), skin change in summer sun (a sunburn skin without blisters vs. a mild sunburn that becomes a tan; β=−0.14, p=0.023), and oral contraceptive use (use vs. nonuse; β=0.15, p=0.002) were significantly associated with circulating 25(OH)D levels.

Conclusions We found that immigrant Filipino women in Korea had high prevalence of deficiency and insufficiency of vitamin D and vitamin D intake, season, skin change and oral contraceptive use were associated with vitamin D status.